Expansion-bit



UNITED STATES PATENT oEEIcE.

ASA WEEKS, OF SOUTH BOSTON, MASSACHUSETTS.

EXPANSION-BIT.

Specification of Letters Patent No. 10,872, dated May 2, 1854.

To all whom t may concern Be it known that I, ASA WEEKS, of South Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in the Construction of Expanding CentenBitS, of which the following is a full, clear, and exact description, reference being had to the drawings making part of this specication, in which# Figure l is a front view of the bit ready for use; Fig. 2, an edge View of the same. Fig. 3 is a view of the same, the cap being removed to show the parts within. Fig. 4f is a modification of the bit which I propose sometimes to make use of; Fig. 5, an edge view of the same; Fig. 6, a view of the same with the cap g removed to show the parts within; Fig. 7, a View of the cap g detached.

Expanding bitsl have been constructed' in which each of the cutters were capable of being drawn out to suit the size of the hole to be bored; in every instance however with which I am acquainted, the cutters have been moved out independently of each other, the distance of each from the center of the bit requiring to be accurately measured whenever they are moved, should one of the cutters be farther from the center of the bit than the other, a smooth hole cannot be bored. y

'Io obviate this inconvenience is the object of my present invention, which consists in so connecting the two cutters with eac-h other that they shall move out and in simult-aneously, each an equal distance from the center of the bit.

To enable others skilled in the art to make and use my invention I will proceed to describe its nature and construction.

In Figs. l, 2 and 3, 0 c', are the cutters, which are furnished with the rack teeth e e', that engage with a small pinion z', the shaft of which passes through the bit :and is furnished with a screw head by means of which the pinion is turned and the cutters are run out as required. The last cog of the rack e upon the cutter c is so enlarged (as seen in Fig. 3) that it cannot enter the spaces in the' In Figs. ll, 5, 6 and 7 is represented a.

modification of the bit which I propose sometimes to adopt. g is a cap secured to the bit by the screw 71., and which is furnished with two small pins m, which enter slots n n in the cutters, and thus hold them in place. When this form of bit is to be operated the screw h is loosened, and the cap g is turned until the bits are run out a suficient distance. The screw It is then tightened, and the tool is ready for use. In certain cases it may be found necessary to prevent the cutters from falling out. For this purpose small pinsV upon the body of the bit, running in grooves in the back of the cut ters, as seen in Fig. 2, may be made use of.

I do not claim an expanding bit, neither do I claim making both of the cutters capable of motion independent of each other, but

That I do claim as my invention and desire to secure by Letters Patent is- The methodherein described of connecting the two cutters with each other, so that they shall move out and in simultaneously and equably as set forth.

ASA IVEEKS.

VVit-nesses SAM. COOPER, JN0. MURDooK. 

